the new ussr illustrated

welcome to the Urbane Society for Skeptical Romantics, where pretentiousness is as common as muck

Archive for the ‘research’ Category

on the explosion of battery research – part one, some basic electrical concepts, and something about solid state batteries…

leave a comment »

just another type of battery technology not mentioned in this post

Okay I was going to write about gas prices in my next post but I’ve been side-tracked by the subject of batteries. Truth to tell, I’ve become mildly addicted to battery videos. So much seems to be happening in this field that it’s definitely affecting my neurotransmission.

Last post, I gave a brief overview of how lithium ion batteries work in general, and I made mention of the variety of materials used. What I’ve been learning over the past few days is that there’s an explosion of research into these materials as teams around the world compete to develop the next generation of batteries, sometimes called super-batteries just for added exhilaration. The key factors in the hunt for improvements are energy density (more energy for less volume), safety and cost.

To take an example, in this video describing one company’s production of lithium-ion batteries for electric and hybrid vehicles, four elements are mentioned – lithium, for the anode, a metallic oxide for the cathode, a dry solid polymer electrolyte and a metallic current collector. This is confusing. In other videos the current collectors are made from two different metals but there’s no mention of this here. Also in other videos, such as this one, the anode is made from layered graphite and the cathode is made from a lithium-based metallic oxide. More importantly, I was shocked to hear of the electrolyte material as I thought that solid electrolytes were still at the experimental stage. I’m on a steep and jagged learning curve. Fact is, I’ve had a mental block about electricity since high school science classes, and when I watch geeky home-made videos talking of volts, amps and watts I have no trouble thinking of Alessandro Volta, James Watt and André-Marie Ampère, but I have no idea of what these units actually measure. So I’m going to begin by explaining some basic concepts for my own sake.

Amps

Metals are different from other materials in that electrons, those negatively-charged sub-atomic particles that buzz around the nucleus, are able to move between atoms. The best metals in this regard, such as copper, are described as conductors. However, like-charged electrons repel each other so if you apply a force which pushes electrons in a particular direction, they will displace other electrons, creating a near-lightspeed flow which we call an electrical current. An amp is simply a measure of electron flow in a current, 1 ampere being 6.24 x 10¹8 (that’s the power of eighteen) per second. Two amps is twice that, and so on. This useful video provides info on a spectrum of currents, from the tiny ones in our mobile phone antennae to the very powerful ones in bolts of lightning. We use batteries to create this above-mentioned force. Connecting a battery to, say, a copper wire attached to a light bulb causes the current to flow to the bulb – a transfer of energy. Inserting a switch cuts off and reconnects the circuit. Fuses work in a similar way. Fuses are rated at a particular ampage, and if the current is too high, the fuse will melt, breaking the circuit. The battery’s negative electrode, or anode, drives the current, repelling electrons and creating a cascade effect through the wire, though I’m still not sure how that happens (perhaps I’ll find out when I look at voltage or something).

Volts

So, yes, volts are what push electrons around in an electric current. So a voltage source, such as a battery or an adjustable power supply, as in this video, produces a measurable force which applied to a conductor creates a current measurable in amps. The video also points out that voltage can be used as a signal, representing data – a whole other realm of technology. So to understand how voltage does what it does, we need to know what it is. It’s the product of a chemical reaction inside the battery, and it’s defined technically as a difference in electrical potential energy, per unit of charge, between two points. Potential energy is defined as ‘the potential to do work’, and that’s what a battery has. Energy – the ability to do work – is a scientific concept, which we measure in joules. A battery has electrical potential energy, as result of the chemical reactions going on inside it (or the potential chemical reactions? I’m not sure). A unit of charge is called a coulomb. One amp of current is equal to one coulomb of charge flowing per second. This is where it starts to get like electrickery for me, so I’ll quote directly from the video:

When we talk about electrical potential energy per unit of charge, we mean that a certain number of joules of energy are being transferred for every unit of charge that flows.

So apparently, with a 1.5 volt battery (and I note that’s your standard AA and AAA batteries), for every coulomb of charge that flows, 1.5 joules of energy are transferred. That is, 1.5 joules of chemical energy are being converted to electrical potential energy (I’m writing this but I don’t really get it). This is called ‘voltage’. So for every coulomb’s worth of electrons flowing, 1.5 joules of energy are produced and carried to the light bulb (or whatever), in that case producing light and heat. So the key is, one volt equals one joule per coulomb, four volts equals 4 joules per coulomb… Now, it’s a multiplication thing. In the adjustable power supply shown in the video, one volt (or joule per coulomb) produced 1.8 amps of current (1.8 coulombs per second). For every coulomb, a joule of energy is transferred, so in this case 1 x 1.8 joules of energy are being transferred every second. If the voltage is pushed up to two (2 joules per coulomb), it produces around 2 amps of current, so that’s 2 x 2 joules per second. Get it? So a 1.5 volt battery indicates that there’s a difference in electrical potential energy of 1.5 volts between the negative and positive terminals of the battery.

Watts

A watt is a unit of power, and it’s measured in joules per second. One watt equals one joule per second. So in the previous example, if 2 volts of pressure creates 2 amps of current, the result is that four watts of power are produced (voltage x current = power). So to produce a certain quantity of power, you can vary the voltage and the current, as long as the multiplied result is the same. For example, highly efficient LED lighting can draw more power from less voltage, and produces more light per watt (incandescent bulbs waste more energy in heat).

Ohms and Ohm’s law

The flow of electrons, the current, through a wire, may sometimes be too much to power a device safely, so we need a way to control the flow. We use resistors for this. In fact everything, including highly conductive copper, has resistance. The atoms in the copper vibrate slightly, hindering the flow and producing heat. Metals just happen to have less resistance than other materials. Resistance is measured in ohms (Ω). Less than one Ω would be a very low resistance. A mega-ohm (1 million Ω) would mean a very poor conductor. Using resistors with particular resistance values allows you to control the current flow. The mathematical relations between resistance, voltage and current are expressed in Ohm’s law, V = I x R, or R = V/I, or I = V/R (I being the current in amps). Thus, if you have a voltage (V) of 10, and you want to limit the current (I) to 10 milli-amps (10mA, or .01A), you would require a value for R of 1,000Ω. You can, of course, buy resistors of various values if you want to experiment with electrical circuitry, or for other reasons.

That’s enough about electricity in general for now, though I intend to continue to educate myself little by little on this vital subject. Let’s return now to the lithium-ion battery, which has so revolutionised modern technology. Its co-inventor, John Goodenough, in his nineties, has led a team which has apparently produced a new battery that is a great improvement on ole dendrite-ridden lithium-ion shite. These dendrites appear when the Li-ion batteries are charged too quickly. They’re strandy things that make their way through the liquid electrolyte and can cause a short-circuit. Goodenough has been working with Helena Braga, who has developed a solid glass electrolyte which has eliminated the dendrite problem. Further, they’ve replaced or at least modified the lithium metal oxide and the porous carbon electrodes with readily available sodium, and apparently they’re using much the same material for the cathode as the anode, which doesn’t make sense to many experts. Yet apparently it works, due to the use of glass, and only needs to be scaled up by industry, according to Braga. It promises to be cheaper, safer, faster-charging, more temperature-resistant and more energy dense than anything that has gone before. We’ll have to wait a while, though, to see what peer reviewers think, and how industry responds.

Now, I’ve just heard something about super-capacitors, which I suppose I’ll have to follow up on. And I’m betting there’re more surprises lurking in labs around the world…

 

 

Advertisements

Written by stewart henderson

July 29, 2017 at 4:00 pm

the strange world of the self-described ‘open-minded’ part two

leave a comment »

  • That such a huge number of people could seriously believe that the Moon landings were faked by a NASA conspiracy raises interesting questions – maybe more about how people think than anything about the Moon landings themselves. But still, the most obvious question is the matter of evidence. 

Philip Plait,  from ‘Appalled at Apollo’, Chapter 17 of Bad Astronomy

the shadows of astronauts Dave Scott and Jim Irwin on the Moon during the 1971 Apollo 15 mission - with thanks to NASA, which recently made thousands of Apollo photos available to the public through Flickr

the shadows of astronauts Dave Scott and Jim Irwin on the Moon during the 1971 Apollo 15 mission – with thanks to NASA, which recently made thousands of Apollo photos available to the public through Flickr

So as I wrote in part one of this article, I remember well the day of the first Moon landing. I had just turned 13, and our school, presumably along with most others, was given a half-day off to watch it. At the time I was even more amazed that I was watching the event as it happened on TV, so I’m going to start this post by exploring how this was achieved, though I’m not sure that this was part of the conspiracy theorists’ ‘issues’ about the missions. There’s a good explanation of the 1969 telecast here, but I’ll try to put it in my own words, to get my own head around it.

I also remember being confused at the time, as I watched Armstrong making his painfully slow descent down the small ladder from the lunar module, that he was being recorded doing so, sort of side-on (don’t trust my memory!), as if someone was already there on the Moon’s surface waiting for him. I knew of course that Aldrin was accompanying him, but if Aldrin had descended first, why all this drama about ‘one small step…’? – it seemed a bit anti-climactic. What I didn’t know was that the whole thing had been painstakingly planned, and that the camera recording Armstrong was lowered mechanically, operated by Armstrong himself. Wade Schmaltz gives the low-down on Quora:

The TV camera recording Neil’s first small step was mounted in the LEM [Lunar Excursion Module, aka Lunar Module]. Neil released it from its cocoon by pulling a cable to open a trap door prior to exiting the LEM that first time down the ladder.

Neil Armstrong, touching down on the Moon -an image I'll never forget

Neil Armstrong, touching down on the Moon – an image I’ll never forget

 

the camera used to capture Neil Armstrong's descent

the camera used to capture Neil Armstrong’s descent

As for the telecast, Australia played a large role. Here my information comes from Space Exploration Stack Exchange, a Q and A site for specialists as well as amateur space flight enthusiasts.

Australia was one of three continents involved in the transmissions, but it was the most essential. Australia had two tracking stations, one near Canberra and the other at the Parkes Radio Observatory west of Sydney. The others were in the Mojave Desert, California, and in Madrid, Spain. The tracking stations in Australia had a direct line on Apollo’s signal. My source quotes directly from NASA:

The 200-foot-diameter radio dish at the Parkes facility managed to withstand freak 70 mph gusts of wind and successfully captured the footage, which was converted and relayed to Houston.

iclez

Needless to say, the depictions of Canberra and Sydney aren’t geographically accurate here!

And it really was pretty much ‘as it happened’, the delay being less than a minute. The Moon is only about a light-second away, but there were other small delays in relaying the signal to TV networks for us all to see.

So now to the missions and the hoax conspiracy. But really, I won’t be dealing with the hoax stuff directly, because frankly it’s boring. I want to write about the good stuff. Most of the following comes from the ever-more reliable Wikipedia – available to all!

The ‘space race’ between the Soviet Union and the USA can be dated quite precisely. It began in July 1956, when the USA announced plans to launch a satellite – a craft that would orbit the Earth. Two days later, the Soviet Union announced identical plans, and was able to carry them out a little over a year later. The world was stunned when Sputnik 1 was launched on October 4 1957. Only a month later, Laika the Muscovite street-dog was sent into orbit in Sputnik 2 – a certain-death mission. The USA got its first satellite, Explorer 1, into orbit at the end of January 1958, and later that year the National Aeronautics and Space Administraion (NASA) was established under Eisenhower to encourage peaceful civilian developments in space science and technology. However the Soviet Union retained the initiative, launching its Luna program in late 1958, with the specific purpose of studying the Moon. The whole program, which lasted until 1976, cost some $4.5 billion and its many failures were, unsurprisingly, shrouded in secrecy. The first three Luna rockets, intended to land, or crash, on the Moon’s surface, failed on launch, and the fourth, later known as Luna 1, was given the wrong trajectory and sailed past the Moon, becoming the first human-made satellite to take up an independent heliocentric orbit. That was in early January 1959 – so the space race, with its focus on the Moon, began much earlier than many people realise, and though so much of it was about macho one-upmanship, important technological developments resulted, and vital observations were made, including measurements of energetic particles in the outer Van Allen belt. Luna 1 was the first spaceship to achieve escape velocity, the principle barrier to landing a vessel on the Moon.

After another launch failure in June 1959, the Soviets successfully launched the rocket later known as Luna 2 in September that year. Its crash landing on the Moon was a great success, which the ‘communist’ leader Khrushchev was quick to ‘capitalise’ on during his only visit to the USA immediately after the mission. He handed Eisenhower replicas of the pennants left on the Moon by Luna 2. And there’s no doubt this was an important event, the first planned impact of a human-built craft on an extra-terrestrial object, almost 10 years before the Apollo 11 landing.

The Luna 2 success was immediately followed only a month later by the tiny probe Luna 3‘s flyby of the far side of the Moon, which provided the first-ever pictures of its more mountainous terrain. However, these two missions formed the apex of the Luna enterprise, which experienced a number of years of failure until the mid-sixties. International espionage perhaps? I note that James Bond began his activities around this time.

the Luna 3 space probe (or is it H G Wells' time machine?)

the Luna 3 space probe (or is it H G Wells’ time machine?)

The Luna Program wasn’t the only only one being financed by the Soviets at the time, and the Americans were also developing programs. Six months after Laika’s flight, the Soviets successfully launched Sputnik 3, the fourth successful satellite after Sputnik 1 & 2 and Explorer 1. The important point to be made here is that the space race, with all its ingenious technical developments, began years before the famous Vostok 1 flight that carried a human being, Yuri Gagarin, into space for the first time, so the idea that the technology wasn’t sufficiently advanced for a moon landing many years later becomes increasingly doubtful.

Of course the successful Vostok flight in April 1961 was another public relations coup for the Soviets, and it doubtless prompted Kennedy’s speech to the US Congress a month later, in which he proposed that “this nation should commit itself to achieving the goal, before this decade is out, of landing a man on the Moon and returning him safely to the Earth.”

So from here on in I’ll focus solely on the USA’s moon exploration program. It really began with the Ranger missions, which were conceived (well before Kennedy’s speech and Gagarin’s flight) in three phases or ‘blocks’, each with different objectives and with increasingly sophisticated system design. However, as with the Luna missions, these met with many failures and setbacks. Ranger 1 and Ranger 2 failed on launch in the second half of 1961, and Ranger 3, the first ‘block 2 rocket’, launched in late January 1962, missed the Moon due to various malfunctions, and became the second human craft to take up a heliocentric orbit. The plan had been to ‘rough-land’ on the Moon, emulating Luna 2 but with a more sophisticated system of retrorockets to cushion the landing somewhat. The Wikipedia article on this and other missions provides far more detail than I can provide here, but the intensive development of new flight design features, as well as the use of solar cell technology, advanced telemetry and communications systems and the like really makes clear to me that both competitors in the space race were well on their way to having the right stuff for a manned moon landing.

I haven’t even started on the Apollo missions, and I try to give myself a 1500-word or so limit on posts, so I’ll have to write a part 3! Comment excitant!

The Ranger 4 spacecraft was more or less identical in design to Ranger 3, with the same impact-limiter – made of balsa wood! – atop the lunar capsule. Ranger 4 went through preliminary testing with flying colours, the first of the Rangers to do so. However the mission itself was a disaster, as the on-board computer failed, and no useful data was returned and none of the preprogrammed actions, such as solar power deployment and high-gain antenna utilisation, took place. Ranger 4 finally impacted the far side of the Moon on 26 April 1962, becoming the first US craft to land on another celestial body. Ranger 5 was launched in October 1962 at a time when NASA was under pressure due to the many failures and technical problems, not only with the Ranger missions, but with the Mariner missions, Mariner 1 (designed for a flyby mission to Venus) having been a conspicuous disaster. Unfortunately Ranger 5 didn’t improve matters, with a series of on-board and on-ground malfunctions. The craft missed the Moon by a mere 700 kilometres. Ranger 6, launched well over a year later, was another conspicuous failure, as its sole mission was to send high-quality photos of the Moon’s surface before impact. Impact occurred, and overall the flight was the smoothest one yet, but the camera system failed completely.

There were three more Ranger missions. Ranger 7, launched in July 1964, was the first completely successful mission of the series. Its mission was the same as that of Ranger 6, but this time over 4,300 photos were transmitted during the final 17 minutes of flight. These photos were subjected to much scrutiny and discussion, in terms of the feasibility of a soft landing, and the general consensus was that some areas looked suitable, though the actual hardness of the surface couldn’t be determined for sure. Miraculously enough, Ranger 8, launched in February 1965, was also completely successful. Again its sole mission was to photograph the Moon’s surface, as NASA was beginning to ready itself for the Apollo missions. Over 7,000 good quality photos were transmitted in the final 23 minutes of flight. The overall performance of the spacecraft was hailed as ‘excellent’, and its impact crater was photographed two years later by Lunar Orbiter 4. And finally Ranger 9 made it three successes in a row, and this time the camera’s 6,000 images were broadcast live to viewers across the United States. The date was March 24, 1965. The next step would be that giant one.

A Ranger 9 image showing rilles - long narrow depressions - on the Moon's surface

A Ranger 9 image showing rilles – long narrow depressions – on the Moon’s surface

the strange world of the self-described ‘open-minded’ – part one

leave a comment »

my copy - a stimulating and fun read, great fodder for closed-minded types, come moi

my copy – a stimulating and fun read, great fodder for closed-minded types, comme moi

I’ve just had my first ever conversation with someone who at least appears to be sceptical of the Apollo 11 moon landing of 1969 – and, I can only suppose, the five subsequent successful moon landings. Altogether, twelve men walked on the moon between 20 July 1969 and December 10 1972, when the crew members of Apollo 17 left the moon’s surface. Or so the story goes.

This conversation began when I said that perhaps the most exciting world event I’ve experienced was that first moon landing, watching Neil Armstrong possibly muffing the lines about one small step for a man, and marvelling that it could be televised. I was asked how I knew that it really happened. How could I be so sure?

Of course I had no immediate answer. Like any normal person, I have no immediate, or easy, answer to a billion questions that might be put to me. We take most things on trust, otherwise it would be a very very painstaking existence. I didn’t mention that, only a few months before, I’d read Phil Plait’s excellent book Bad Astronomy, subtitled Misconceptions and misuses revealed, from astrology to the moon landing ‘hoax’. Plait is a professional astronomer who maintains the Bad Astronomy blog and he’s much better equipped to handle issues astronomical than I am, but I suppose I could’ve made a fair fist of countering this person’s doubts if I hadn’t been so flabbergasted. As I said, I’d never actually met someone who doubted these events before. In any case I don’t think the person was in any mood to listen to me.

Only one reason for these doubts was offered. How could the lunar module have taken off from the moon’s surface? Of course I couldn’t answer, never having been an aeronautical engineer employed by NASA, or even a lay person nerdy enough to be up on such matters, but I did say that the moon’s minimal gravity would presumably make a take-off less problematic than, say, a rocket launch from Mother Earth, and this was readily agreed to. I should also add that the difficulties, whatever they might be, of relaunching the relatively lightweight lunar modules – don’t forget there were six of them – didn’t feature in Plait’s list of problems identified by moon landing skeptics which lead them to believe that the whole Apollo adventure was a grand hoax.

So, no further evidence was proffered in support of the hoax thesis. And let’s be quite clear, the claim, or suggestion, that the six moon landings didn’t occur, must of necessity be a suggestion that there was a grand hoax, a conspiracy to defraud the general public, one involving tens of thousands of individuals, all of whom have apparently maintained this fraud over the past 50 years. A fraud perpetrated by whom, exactly?

My conversation with my adversary was cut short by a third person, thankfully, but after the third person’s departure I was asked this question, or something like it: Are you prepared to be open-minded enough to entertain the possibility that the moon landing didn’t happen, or are you completely closed-minded on the issue?

Another way of putting this would be: Why aren’t you as open-minded as I am?

So it’s this question that I need to reflect on.

I’ve been reading science magazines on an almost daily basis for the past thirty-five years. Why?

But it didn’t start with science. When I was kid, I loved to read my parents’ encyclopaedias. I would mostly read history, learning all about the English kings and queens and the battles and intrigues, etc, but basically I would stop at any article that took my fancy – Louis Pasteur, Marie Curie, Isaac Newton as well as Hitler, Ivan the Terrible and Cardinal Richelieu. Again, why? I suppose it was curiosity. I wanted to know about stuff. And I don’t think it was a desire to show off my knowledge, or not entirely. I didn’t have anyone to show off to – though I’m sure I wished that I had. In any case, this hunger to find things out, to learn about my world – it can hardly be associated with closed-mindedness.

The point is, it’s not science that’s interesting, it’s the world. And the big questions. The question – How did I come to be who and where I am?  – quickly becomes – How did life itself come to be? – and that extends out to – How did matter come to be? The big bang doesn’t seem to explain it adequately, but that doesn’t lead me to imagine that scientists are trying to trick us. I understand, from a lifetime of reading, that the big bang theory is mathematically sound and rigorous, and I also know that I’m far from alone in doubting that the big bang explains life, the universe and everything. Astrophysicists, like other scientists, are a curious and sceptical lot and no ‘ultimate explanation’ is likely to satisfy them. The excitement of science is that it always raises more questions than answers, it’s the gift that keeps on giving, and we have human ingenuity to thank for that, as we’re the creators of science, the most amazing tool we’ve ever developed.

But let me return to open-mindedness and closed-mindedness. During the conversation described above, it was suggested that the USA simply didn’t have the technology to land people on the moon in the sixties. So, ok, I forgot this one: two reasons put forward – 1, the USA didn’t have the technological nous; 2, the modules couldn’t take off from the moon (later acknowledged to be not so much of an issue). I pretty well knew this first reason to be false. Of course I’ve read, over the years, about the Apollo missions, the rivalry with the USSR, the hero-worship of Yuri Gagarin and so forth. I’ve also absorbed, in my reading, much about spaceflight and scientific and technological development over the years. Of course, I’ve forgotten most of it, and that’s normal, because that’s how our brains work – something I’ve also read a lot about! Even the most brilliant scientists are unlikely to be knowledgeable outside their own often narrow fields, because neurons that fire together wire together, and it’s really hands-on work that gets those neurons firing.

But here’s an interesting point. I have in front of me the latest issue of Cosmos magazine, issue 75. I haven’t read it yet, but I will do. On my shelves are the previous 74 issues, each of which I’ve read, from cover to cover. I’ve also read more than a hundred issues of the excellent British mag, New Scientist. The first science mag I ever read was the monthly Scientific American, which I consumed with great eagerness for several years in the eighties, and I still buy their special issues sometimes. Again, the details of most of this reading are long forgotten, though of course I learned a great deal about scientific methods and the scientific mind-set. The interesting point, though, is this. In none of these magazines, and in none of the books, blogs and podcasts I’ve consumed in about forty years of interest in matters scientific, have I ever read the claim, put forward seriously, that the moon landings were faked. Never. I’m not counting of course, books like Bad Astronomy and podcasts like the magnificent Skeptics’ Guide to the Universe, in which such claims are comprehensively debunked.

The SGU podcast - a great source for exciting science developments, criticism of science reporting, and debunking of pseudo-science

The SGU podcast – a great source for exciting science developments, criticism of science reporting, and debunking of pseudo-science

Scientists are a skeptical and largely independent lot, no doubt about it, and I’ve stated many times that scepticism and curiosity are the twin pillars of all scientific enquiry. So the idea that scientists could be persuaded, or cowed into participating in a conspiracy (at whose instigation?) to hoodwink the public about these landings is – well let’s just call it mildly implausible.

But of course, it could explain the US government’s massive deficit. That’s it! All those billions spent on hush money to astronauts, engineers, technicians (or were they all just actors?), not to mention nosey reporters, science writers and assorted geeks – thank god fatty Frump is here to make America great again and lift the lid on this sordid scenario, like the great crusader against fake news that he is.

But for now let’s leave the conspiracy aspect of this matter aside, and return to the question of whether these moon landings could ever have occurred in the late sixties and early seventies. I have to say, when it was put to me, during this conversation, that the technology of the time wasn’t up to putting people on the moon, my immediate mental response was to turn this statement into a question. Was the technology of the time up to it? And this question then turns into a research project. In other words, let’s find out, let’s do the research. Yay! That way, we’ll learn lots of interesting things about aeronautics and rocket fuel and gravitational constraints and astronaut training etc, etc – only to forget most of it after a few years. Yet, with all due respect, I’m quite sure my ‘adversary’ in this matter would never consider engaging in such a research project. She would prefer to remain ‘open-minded’. And if you believe that the whole Apollo project was faked, why not believe that all that’s been written about it before and since has been faked too? Why believe that the Russians managed to get an astronaut into orbit in the early sixties? Why believe that the whole Sputnik enterprise was anything but complete fakery? Why believe anything that any scientist ever says? Such radical ‘skepticism’ eliminates the need to do any research on anything.

But I’m not so open-minded as that, so in my dogmatic and doctrinaire fashion I will do some – very limited – research on that very exciting early period in the history of space exploration. I’ll report on it next time.

Written by stewart henderson

February 25, 2017 at 12:34 pm

adventures in second language acquisition – an intro to the usage-based hypothesis of language learning

leave a comment »

don't you just hate it when slide presentations on grammar contain grammar errors

don’t you just hate it when slide presentations on grammar contain grammar errors

So now I’m going to describe and reflect on a rather more interesting video by two academics and teachers, Marjo Mitsutomi, a specialist in SLA, and Minna Kirjavainen, who researches first language acquisition. They’re working in the teaching of English in Osaka, and they’re describing the uni course they’ve just set up there. Kirjavainen, the first speaker, describes her research as being on ‘the acquisition of syntax and morphology in monolingual, typically developing children, from about the ages two to six’. So now for some definitions. How does syntax differ from grammar, and what is morphology? A rough answer is that a grammar involves everything about how a language works, which includes syntax, which is essentially about how words are ordered in sentences. Morphology is often described as the corollary of syntax. Grammar can be divided into syntax, the external economy of words (i.e. in sentences), and morphology, the internal economy of words (i.e. from morphemes). For example, ‘robbed’ contains the verb ‘rob’ plus the unit of meaning ‘-ed’, or ‘-bed’, which means ‘in the past’. But presumably ‘went’ is made up of two morphemes, ‘go’ and ‘in the past’, both of which are in a sense hidden in the word?

Kirjavainen describes herself as coming from the ‘usage-based, constructivist view-point’, and says

‘this means that I don’t assume there’s innate syntactic components in the child’s mind like many first language and second language acquisition researchers do. Instead, the usage-based viewpoint assumes that language exposure and general cognitive processes result in language acquisition in children.’

A slide accompanying this anouncement indicated that Michael Tomasello is one of the major developers of this approach. So I’ll need to familiarise myself with Tomasello’s work, especially as I’m currently reading Steven Pinker’s The language instinct, which appears to be an attempt to popularise Chomsky’s universal grammar theories. Chomsky and Pinker argue that there is something innate about grammar, though just what it is is hard to capture.

Kirjavainen is of the view that a child’s general cognitive processes (e.g. pattern finding, analogy-making and categorisation) together with exposure to language, lead to competent language acquisition. She argues that these processes are effective for non-linguistic tasks, so the same mechanisms are sufficient for decoding the language they hear and want to use. She divides her inquiry into first language acquisition into three questions:

  1. how do children learn to speak their native language?
  2. what kind of things do children pay attention to when they learn their native language?
  3. how do caregivers talk to children? What effect does it have on children’s language development?

Firstly, children pay a lot of attention to language input, and apparently research is starting to show that it’s not just lexical items but grammatical structures that children mirror from caregivers. The most frequently used grammatical structures of caregivers are the ones used earliest by children, and they then become the most used by children. So the ambient language heavily influences the child’s language development. The constructivists also argue that syntactic constructions are built on the language that children already know. So they chunk things together and try them out for effective communication with those around them, they absorb responses and corrections and adjust their language accordingly. Examples are ‘Mummy’, ‘I want mummy’, ‘Mummy do it’ ‘I want mummy do it’, ‘I want mummy to do it’.

All of this makes a lot of sense to me prima facie. Mitsotomi, who next takes up the talk, is of Finnish background like Kirjavainen, but with a more pronounced accent, having learned English later in life. She begins by mentioning the critical period hypothesis for SLA, which might be the subject of a future post. Her concern is in how SLA is affected not only by the towering presence of the learner’s L1, but by many other life experiences. So given these influences and possible constraints how do we create a space and an atmosphere conducive to SLA? Also, what does SLA mean to the identity of learners, and how is it that some acquire an L2 more quickly and effectively than others?

Kirjavainen then continues by introducing what might be seen as the obstacles to a collaboration between first and second language theorists. First, some linguists argue that there are inherent differences between first and second language learning. She lists three (out of many) common assumptions about these differences:

  1. all (typically developing) children learn to speak their L1 natively, whereas most people (with normal cognitive skills) don’t learn their L2 to a native-like standard
  2. children learn their L1 very quickly whereas it takes L2 learners years to master their target language
  3. L1 learners make few errors in comparison to L2 learners, i.e. children find it easier to learn the grammatical rules of their language, whereas L2 learners find it difficult to learn these rules

Kirjavainen questions the first assumption, first on the basis of vocabulary – a child’s L1 vocab will depend on her socio-economic background, the level of education, experience and language competence of those she’s learning from and other such factors. These factors also affect syntax, and she described a study of native speakers’ knowledge of and proficiency in the passive construction. The study compared the proficiency of university teaching staff (academics) with non-teaching staff. They were tested on their understanding of active and passive sentences based on pictures, a fairly easy test, and it was found that while both teaching and non-teaching staff had full understanding of the active constructions, only the academics had full understanding of the passive construction. The non-teaching staff were significantly below full understanding. The general point here is that not all native speakers know all the grammatical rules of their L1, and that it depends more on regular usage than is sometimes admitted.

Next Kirjavainen gets stuck into the claim that children learn their native language quickly. She points out that an average 5 year old is quite a competent L1 user, but far from having adult proficiency. She then does a breakdown of how many hours a day children have spent, up to the age of five, exposed to and using the L1. That’s 5 years@6-14 hours a day of exposure, and about 3.5 years@8-14 hours a day in using the language. Conclusion: it takes children years to reach a relatively high level of L1 proficiency.

All of this strikes me as really thought-provoking stuff, and some of the thoughts provoked in me are memories of my callow youth – for example an occasion when as a 15 year-old or so I found myself at a party full of uni students types, all a few years my senior, and was awed by their vocabulary and language proficiency, and fearful that I’d get roped into conversation and be mocked for my verbal incompetence. So, again, I’m finding Kirjavainen’s arguments persuasive here at first blush.

The third assumption is more or less demolished by Kirjavainen as she cites research by herself and others to show that children make lots of errors, especially between the ages of 18 months and 4 years – these include pronoun errors, omission of infinitival to, agreement errors, subject omissions and verb inflection errors. Even at five and upwards there are mistakes with past tense, relative clauses and complement clause constructions. A complement clause? I’ve only just heard of them, but let me explain.

Here are two examples of complement clauses, taken from Kidd et al, 2007.

(1)  That Rufus was late angered his boss.

(2)  Rufus could see that he had angered his boss.

The complement clauses are underlined. The first here functions as the subject of an ‘argument’ sentence, the second as the object. The second sentence is described as an unmarked case, in which the complementiser that is optional and generally not used in naturalistic speech. There are many other forms of complement clause construction, so I won’t get bogged down by exploring them here.

So this has been an enlightening post for me, and an enlightening view of a new (to me) usage-based constructivist view of language acquisition. Next time I’ll report on the latter part of this talk, which will focus more on the implications for SLA.

just a thought to end with

just a thought to end with

Written by stewart henderson

January 30, 2017 at 3:25 pm

Our recent power outage – how to prevent a recurrence. part 1 – preliminary remarks

leave a comment »

transmission-towers

Canto: So we’re tasked with solving the problem or problems in SA’s energy system.

Jacinta: We are? What problem? Or should I say crisis, what crisis?

Canto: That’s a good question Jass, because as you know the first step in finding a solution is to define the problem.

Jacinta: Yes I knew that. So we’re talking about how all the power died for a period of – what, 24 hours or so, statewide here in South Africa.

Canto: South Australia, don’t confuse our international readers. So I’ve heard the crisis framed in a number of different ways. First, in terms of the SA government’s irresponsible, unrealistic go-it-alone pursuit of risky renewable energy. Second, in the more or less opposite terms of other states’ and especially the federal govt’s foot-dragging and negative approach to said energy, leaving SA unsupported. Third, in terms of privatisation – a number of electrical pylons fell down like ninepins in the outback, because, it’s claimed, the private owners are pursuing profits over infrastructure maintenance. And a fourth and most comprehensive framing invokes climate change itself – SA was subjected to an unprecedented weather event likely caused by the emissions our gallant state government is trying to reduce..

Jacinta: And our little Torrens River has been torrenting like the mighty Amazon.

Canto: Yeah right. So with all these and more framings of the problem, it looks like we’ll have to spend a few posts on this issue.

Jacinta: Or a lifetime. But yes let’s try to be thorough. And positive. I thought we might start with the 9-point plan for solutions to complex problems which we found in the enlightening book The origin of feces by Stuart Waltner-Toews, and which was presented in simplified form on the Solutions OK blog.

1. What is the problem situation or issue? How did it come to be a problem?

2. Who are the stakeholders? What do they care about? Where are they coming from (motives, investments)? What are the agreements, discords among them?

3. What are the stories being told by these different stakeholders re their roles and concerns in the problem?

4. What’s our best systematic, scientific understanding of the situation/problem?

5. What’s our best understanding of the social & cultural issues to be addressed?

6. How are 4 & 5 related? How do they constrain or support each other?

7. What are the scenarios and narratives here that people most connect with? On what things can we agree on? What are the power relations between people who agree or disagree? Given these constraints and acknowledgements what do we realistically expect that we can do?

8. What course of action, governance structure and monitoring system will best enable us to implement our plans and move towards our goals?

9. Implement. Monitor. Adjust. Learn. Re-Start.

Canto: Yeah, that’s pretty comprehensive all right, maybe too comprehensive.

Jacinta: No I think it’s a good basis. Take point 1. What’s the problem? That’s easy. The problem is that SA had all its power cut for the best part of a day, and although many are saying this was a one-off, freak event, many others are saying it could happen again and that SA’s the most vulnerable state, it wouldn’t have happened to any other state.

Canto: Though I think our Premier said the exact opposite, it could’ve happened anywhere. Lots of conflicting narratives and opinions. So let’s get started.

Jacinta: Well let me first say that, whatever the cause, we are experiencing extreme weather here for October – rainy and stormy conditions which have certainly never been experienced here in a good long lifetime. And right now we’re got rain and strong wind conditions. There’s been little let-up for some time.

Canto: Interesting – we’re only a few days into October, but the average rainfall for September in Adelaide, since records have been kept, is about 58 millimetres. This year it was over 130 millimetres. October, though, might be the most interesting month for records. Certainly I can’t recall anything like this, and we have flooding in many parts of the state.

Jacinta: So we have extreme weather conditions, and the direct cause of the outage, according to our Premier, was freak weather conditions north of Adelaide, including two tornados which knocked over transmission towers near Melrose. More than 20 transmission lines were damaged. The question being asked, of course, is how could these storms knock out the power for a whole vast state for a long period? What were the back-up arrangements?

Canto: Well the back-up apparently relies on two interconnectors to the east coast. Presumably there must be some arrangement so that when local power isn’t forthcoming, the interconnectors receive a signal to transmit. However, only one was operational at the time of the outage. Now I don’t really understand this interconnector thing and how they work. I’m not clear on why one interconnector was shut down and why the other one didn’t just do the job. Is it just a matter of ‘firing up’ an interconnector and a whole state’s lights come back on? How simple or complex is it?

Jacinta: And what, if anything, has this got to do with renewable energy and the shutting down of the coal power station in Port Augusta?

Canto: We might get to that later. I haven’t been able to find exactly how interconnectors work, and nothing much at all on interconnectors in Australia, but currently in the UK there are four interconnectors, linked to France, the Netherlands, Northern Ireland and the Republic of Ireland, of which the France one is largest, with 2GW capacity. It would be interesting to know the capacity of the two interconnectors linking us to the east, and whether that has any relevance. Anyway, these interconnectors are spruiked as providers of energy security and flexibility, so the more interconnectors the better. Maybe there’s a case for having a third interconnector, so that we’re never, or rarely reduced to having just one to rely on.

Jacinta: So why did we have no power? Why didn’t the interconnector provide it for so long? Or was it the interconnector that provided it, or was it the local system?

Canto: Well there was certainly local work going on from the start, as soon as conditions allowed, to fix local faults, but I can’t find too much info on the role of the interconnector. However, word has just come out that there’ll be a state inquiry into South Australia’s unique situation, so maybe there’s no point in us continuing this conversation.

Jacinta: Wait up, I think it might be fun speculating on and researching the matter, and then comparing our findings with the inquiry.

Canto: Which’ll come out in, what, five years?

Jacinta: An unnecessarily jaded remark. So let’s get stuck into some research, and look for solutions, always keeping in mind that 9-point plan.

 

Written by stewart henderson

October 4, 2016 at 7:54 pm

women in science, solutions, and why nobody reads my blog, among other things

with 4 comments

img_0417

Okay I’ve written facetiously about getting rid of men, or seriously (but facetiously) reducing their proportion of the populace, but in future I want to look at real solutions to a problem that I think is already being addressed but far too patchily and slowly – the problem of male power and dominance. The general solution, of course, is the ascent of woman, to paraphrase Jacob Bronowski via Darwin, and how to promote and quicken it. (Incidentally I’ve just discovered that ‘The Ascent of Woman’ is a four part documentary on women’s history, recently produced for the BBC by Dr Amanda Foreman – look forward to watching it).

However, before continuing I want to issue a plea for help. My blog, which I’ve been writing for many years now, has never had much of a readership, due probably to my inability to network, or even communicate much with others (I’d rather not think it’s anything to do with my writing skills). However, last month even that minuscule readership virtually collapsed, as I recorded my lowest number of hits since my first month of blogging. I’ve soldiered on, but now at the end of September I find this month’s numbers even worse. I feel I need to make a decision about the blog’s future – How do I increase the numbers? Does the blog need a makeover? Can I blame the attention-span of others? I find if I write short pieces, they don’t really cover anything in depth, but I know also that the in-depth pieces, the ones I work on hardest, often get the least attention. Should I just give up and go back to journal writing? At least that way I won’t be faced with the world’s indifference…

Anyway, enough about me – it’s interesting that when you start focusing on an issue, you hear about it everywhere, everybody seems to be talking about it. Today, listening to a podcast of the ABC Science Show, I heard that teenagers are our biggest killers, worldwide, predominantly through motor vehicle accidents. And of course we’re talking largely of male teenagers. The researcher announcing this was female, and, typical female, she was complaining about us tackling this old problem (this has been the global situation for some sixty years) in the same old piecemeal way, rather than though global collaboration in researching and trying to figure out workable solutions to what is clearly a global problem. It was clear from this passionate speaker (and mother of teenage children) that with more females leading research in this and other fields, we’ll get more collaboration and quicker and more effective solutions. And when Robyn Williams, our honourable Science Show anchor, asked the researcher a double-barrelled question – is this teenage problem a male one, and should teenage boys be banned from driving? – her honourable response was ‘yes, and yes’.

The question is – would a law specifically targeting boys/young men as drivers ever be implemented? Of course, many males would describe it as discriminatory. And of course it does discriminate, because the statistics are clear. But why, a young male might ask, should I be treated as a statistic? I’m not like other young men.

It’s a valid point, and I can’t see an obvious way of screening out the potentially safe young men from the potentially dangerous ones. So all we could acceptably do is raise the driving age for all, preferably globally, which would effectively discriminate against the statistically safer drivers, the females. Still, I like the idea of a push, led in the main by women, for a discriminatory driving age policy backed by science. It would raise the profile of the issue, bring women together in an excellent cause, potentially save lives, and feature as another small episode in the ascent of women.

Of course it wouldn’t solve the terrible wee problem of young kids stealing cars and killing and maiming others and themselves for pumped-up kicks…

Written by stewart henderson

October 1, 2016 at 8:39 am